prostate

Definition: The prostate is located in the pelvis between the bladder neck (base of prostate) and the urogenital diaphragm and the muscle levator ani (apex of prostate).

The prostate function is to conduct urine and to add nutritional secretions to sperm to form semen during ejaculation. This funnel shaped organ weight approximatively 20 g and measures 4 x 3 x 2 cm.

The apex of prostate contains some muscle fibers from urogenital diaphragm.

The male prostate gland is located below the bladder. The seminal vesicles are located posterior to the prostate. The urethra exits from the bladder and traverses the prostate before exiting to the penile urethra.

The normal prostate is composed of glands and stroma. The glands are seen in cross section to be rounded to irregularly branching. These glands represent the terminal tubular portions of long tubuloalveolar glands that radiate from the urethra.

The glands are lined by two cell layers: an outer low cuboidal layer and an inner layer of tall columnar mucin-secreting epithelium. These cells project inward as papillary projections. The fibromuscular stroma between the glands accounts for about half of the volume of the prostate.

As a male ages, there are more likely to be small concretions within the glandular lumina, called ``corpora amylacea``, that represent laminated concretions of prostatic secretions. The glands are normally separated by stroma.

The prostate is surrounded by a thin layer of connective tissue that merges with surrounding soft tissues, including nerves. There is no distinct capsule.